This invention relates to reduced-pulsation pumping systems. More particularly, this invention relates to pulsation-reducing pumping systems which provide superior pumping capability through the reduction of fluid pulsations and cavitation tendencies. In addition, this invention relates to gear pumps having increased operational safety and superior field configurability.
Fluid pulsation is a hallmark of conventional positive-displace gear pumps. Flow pulsation during the operation of such pumps is often associated with damage to piping, meters, valves, and instrumentation. In addition, flow pulsation in essential production processes often contributes to poor and/or inconsistent product quality, thus producing off-spec waste or inferior final results. Particularly problematic is the reduced accuracy of flow metering and measurement devices (especially in pulse-sensitive coriolis flow meter apparatus) that result from fluid pulsation. A means for directly reducing flow pulsation and similar “noise” within the output of positive displacement pumps would be of great benefit to many fields.
Gear pump cavitation is associated with reduced pumping performance and erosion of internal pumping surfaces. Cavitation generally results from the sudden formation and collapse of low-pressure bubbles in the fluid being pumped. Increasing gear pump performance by reducing the tendency of a given pump to experience cavitation at elevated pump speeds would be of great benefit in many fields, including asphalt pumping.
Asphalt is a cementitious material widely used in numerous industrial applications including paving and roofing. Many asphalt-installation procedures require the asphaltic materials to be heated into a workable molten state prior to use. It is common for such hot asphalt materials to be maintained at temperatures ranging between about 100 and 200 degrees Celsius. Specialized pumping apparatus is frequently used to transfer and meter such hot asphaltic materials.
Numerous safety hazards arise from the handling of asphalt in an elevated temperature. Asphalt has a large thermal capacity and therefore poses a high potential for serious injury should an uncontrolled release of the materials occur. An ideal pumping apparatus would prevent failures by controlling any overpressures occurring within an asphalt pumping system, for the full duration of the material transfer, including forward, reverse, and high-volume pumping operations.
Conventional asphalt-pump designs provide limited or marginal pressure safety during operation, and are not readily modifiable using straightforward engineering. Furthermore, conventional asphalt-pump designs have remained substantially unchanged over time and currently offer little in terms of adaptability/field configurability. Improvements in asphalt pumping systems to provide safe and efficiently adaptable designs would also be of great benefit to many.